Occupationally disaggregated manpower statistics are invaluable for economic analysis and manpower planning, but administrative occupational groupings are often inappropriate for these uses. Administrative occupational groupings are unreliably defined by subjective assessment of similarity of job types. Observations of mobility between 161 condensed KOS (Key Occupations for Statistical Purposes) from the 1975, 1977, 1979, 1981, and 1983 Labour Force Surveys input into an Intramax regionalisation procedure produce occupational groups defined by internal mobility relations. This is a repeatable and more reliable method for the definition of occupational groupings. The twenty-eight groupings produced by the procedure reveal some interesting and in some cases disturbing features of the Office of Population Censuses and Surveys and Department of Employment occupational groupings. The procedure could reasonably form the basis of a better administrative classification system incorporating the effects of structural changes in labour demand. Just like travel to work areas, functional occupations could be updated after each census.